Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
200611
CRED Optical Validation Data at the islands of Ofu and Olosega in American Samoa, 2004 to Support Benthic Habitat Mapping (TOAD)
Video imagery, track line navigation files, and log sheets
http://www.soest.hawaii.edu/pibhmc/
http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_ofu_optical.htm
Optical validation data were collected using a Tethered Optical Assessment Device (TOAD), an underwater sled
equipped with an underwater digital video camera and lights. Data were collected in American Samoa, around the
islands of Ofu and Olosega to support Benthic Habitat Mapping efforts during NOAA Ship Oscar Elton Sette cruise
OES0402, from February 4-14, 2004.
These data provide optical observations that will be correlated with bathymetry and acoustic backscatter
imagery to develop a benthic habitat map of Ofu and Olosega. Refer to supplemental information for description of
instrument and survey.
Ofu and Olosega Islands are part of the Manu'a Island group in American Samoa, situated
approximately 100 km northeast of Tutuila and 20km west of Ta'u. Centered at 14.17 degrees S, 169.65 degrees W,
the twin islands have very little human settlement. Ofu and Olosega are steep, volcanic high islands that lie only
75 m apart and are connected by a bridge and road built across the shallow reef flat. Shallow multibeam mapping was
conducted in 2004 and revealed approximately 60 km2 of previously uncharted bank top (greater than 300 m) that
extends 0.2 to 2 km from shore and then drops abruptly to oceanic depths. An underwater portion of the National Park
of American Samoa, which has exceptionally prolific coral growth, is located on the south shore of Ofu Island.
Optical validation data were collected using the Tethered Optical Assessment Device (TOAD), a sled equipped with
underwater video camera and lights. These data are used to provide ground-truth validation for benthic habitat maps
based on multibeam echosounder surveys. Camera sled deployments were conducted at night, usually between 1800 and
midnight. The duration of each tow varied but averaged about 40 minutes of bottom time at a given location. The
camera sled was deployed from the port J-frame mounted amidships on the NOAA Ship Oscar Elton Sette. At each station
the ship was positioned with the wind on the port side and drifted downwind; occasional light turns were applied to
the ship's screws if necessary to reduce the ship's motion. The TOAD was lowered slowly to the bottom by the deck
crew using a capstan. The operator monitored a live video feed from the camera and began recording data on a video
tape recorder. When the camera reached bottom the deck crew was notified by radio to stop lowering. The operator
continued to monitor the vehicle and provided commands to raise or lower it to keep the camera just above the bottom.
Equipment Description: The TOAD was deployed from the lower arm of the vessel's port side J-frame. The TOAD is a
camera sled based on the Guildline MiniBat model 8820 tow body. The frame has been extensively modified from its
original configuration and was equipped with an ROS model 54-00100-13 color underwater video camera as the primary
data collection instrument. The ROS camera was mounted to point at approximately a 45 degree angle toward the seafloor.
A Deep Sea Power and Light model 2050 MultiSeaCam low-light color video camera was also mounted on the sled and aimed
straight ahead. The signal from this camera was fed to a second video monitor to provide warning of underwater
obstructions the sled might be headed for. Illumination was provided by two 500 W DeepSea Power and Light Multi-SeaLite
model 1050 underwater lights mounted on the original sled frame. The lights were located near the base and each side
of the sled to provide the maximum possible horizontal distance from the ROS camera. Cable between the sled and the
surface consisted of a underwater electrical cable (cable 1, blue in color) with a separate load-bearing line to
support the sled frame. The electrical cable was clipped to the line at regular intervals upon deployment and removed
upon recovery. The load-bearing line was led to the starboard capstan on the aft deck. All TOAD surface components
were located in the Dry Lab in an equipment rack on the after bulkhead.
Name & address of person collecting data:
Joyce Miller
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
Honolulu, HI 96818
Data Files: Video data were recorded on a video tape recorder. The position of the camera sled was recorded in WGS-84
using Guildline MiniBat In-Tow data acquisition software and a data feed from a shipboard Northstar Chartplotter.
File naming convention: Each tow is given a name consisting of a three-letter designator for the island area, followed
by a two-digit year and a three-digit tow number, which increments by one for each new tow around that island. During
OES0402 (NOAA Ship Oscar Elton Sette's 2nd cruise in calendar year 2004) the consecutive tows at Tutuila started at
TUT04000. For following cruises, the tow numbers will increment by 100, so the first tow on the next cruise to Tutuila
in 2004 will be tow number TUT04100. Video tape labels, the navigation files (*.glo) and paper log forms are annotated
with the tow name and number, e.g., TUT04012. If the navigation file is edited during processing the file name has a
suffix 'a' added. For example, for a navigation data file named TUT04012a.glo, the 'a' would indicate that metadata
were extracted from the navigation data and recorded to a file with the same name as the navigation file except that a
file type of '.met' was appended; for example, 'TUT04012a.glo.met.
Time Correlation: All times are based on UTC. Two clocks were manually synchronized prior to starting data collection;
the clock in the video character generator that was used to annotate the video tape, and the clock in the TOAD data
acquisition computer. These clocks were set to UTC at the beginning of each evening's operations.
Resource Description: Digital video imagery that is geo-referenced to navigation files.
20040204
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ground condition
Complete
None planned
-169.705274
-169.583687
-14.133505
-14.203385
CoRIS Theme Thesaurus
EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Photographic analysis > Videography
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Mapping
None
Tethered Optical Assessment Device (TOAD)
Underwater video
OES0402
CoRIS Discovery Thesaurus
Visual Images > Habitats
ISO 19115 Topic Category
environment
007
biota
002
CoRIS Place Thesaurus
OCEAN BASIN > Pacific Ocean > Manu'a Group > Ofu Island (14S169W0013)
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Ofu Island (14S169W0013)
OCEAN BASIN > Pacific Ocean > Manu'a Group > Olosega Island (14S169W0014)
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Olosega Island (14S169W0014)
CoRIS Region
AmSam
None
Please acknowledge the NOAA Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center as
the source of this information.
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
John Rooney
mailing and physical address
NOAA IRCNMFS/PIFSC/CRED1845 WASP Blvd., Building 176
Honolulu
HI
96818808 725-5360808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
Pacific Island Benthic Habitat Mapping Center, Coral Reef Ecosystem Division (CRED), Pacific Islands
Fisheries Science Center (PIFSC), NOAA
Not applicable
Unclassified
Not applicable
Unspecified
Complete
The horizontal position accuracy for the camera sled position is estimated at
plus or minus 100 meters. There are three primary sources of this error. The ship's positioning is based on GPS
SPS, often called standalone or non-differential GPS positioning. SPS has a measured accuracy of under 5 meters.
The position of the GPS antenna is used; no attempt is made to translocate this position to that of the tow block
from which the camera is deployed. The difference between the tow block and the antenna is about 14 meters. The
largest source of error is uncertainty associated with the sled's position relative to the tow block.
After a tow was completed the video tape data was reviewed by spot-checking the master to verify
that data were recorded. A backup copy of the tape is made at that time as well. Navigation data were copied from
the acquisition computer to the data archive. A metadata extractor (gloFilter.py, version 3/17/06) was run to
summarize the navigation data and test for errors. If errors were detected in a record, a copy of the data file was
made (the 'a.glo' file mentioned above), that record was automatically flagged as invalid, and corrections were made
if possible. This file's header was updated to document what type of processing occurred. A metadata file was
recorded in the data archive in the same location as the navigation data. Processed navigation data were then imported
to ArcGIS 9.x.
20060331
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
John Rooney
mailing and physical address
NOAA IRCNMFS/PIFSC/CRED1845 WASP Blvd., Building 176
Honolulu
HI
96818808 725-5360808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
Downloadable Data
These data are not to be used for navigational purposes. NOAA makes no warranty regarding these
data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability
for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function
on a particular system.
ASCII
Each comma-delimited record contains information on the UTC date and time, latitude,
longitude, velocity north and east of the ship, water depth of the seafloor below the transducer (to find the total
depth from the water surface to the seafloor add 5 m to these values to account for the depth of the tranducer)
layback, and wing angle.
List of navigation files:
The shapefiles showing camera sled tracks listed below consist of a collection of files with the names listed
below, followed by these extensions: .dbf, .shp, .shx, and .prj. All file types are necessary to properly displaying
the source data.
List of Navigation files:
ofu04002.glo
ofu04003.glo
ofu04011a.glo
ofu04012.glo
ofu04013.glo
ofu04014.glo
ofu04017.glo
ofu04018.glo
ofu04019.glo
ofu04024.glo
ofu04025.glo
ofu04026.glo
ofu04027a.glo
CD-ROM
ISO 9660
avihttp://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_optical_data.html
None
Data is available in VHS format. Contact distributor.
A total of 47 separate segments of video data are available covering 25.6 linear kilometers of seabed. These data
were recorded on 9 video tapes
List of video tapes:
TAU04000/OFU04002, VHS, Master
OFU04003/TAU04004-005, VHS, Master
TAU04010/OFU04011, VHS, Master
OFU04012-014, VHS, Master
OFU04017-019, VHS, Master
OFU04024-025, VHS, Master
OFU04026-027, VHS, Master
TAU04000/OFU04002a, Mini DV, Master and Backup
TAU04000/OFU04002b, Mini DV, Master and Backup
OFU04003/TAU04004-005a, Mini DV, Master and Backup
OFU04003/TAU04004-005b, Mini DV, Master and Backup
TAU04010/OFU04011a, Mini DV, Master and Backup
TAU04010/OFU04011b, Mini DV, Master and Backup
OFU04012-014a, Mini DV, Master and Backup
OFU04012-014b, Mini DV, Master and Backup
OFU04017-019a, Mini DV, Master and Backup
OFU04017-019b, Mini DV, Master and Backup
OFU04024-025a, Mini DV, Master and Backup
OFU04024-025b, Mini DV, Master and Backup
OFU04026-027, Mini DV, Master and Backup
None
20140423
20100504
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
mailing and physical address
NOAA IRCNMFS/PIFSC/CRED1845 WASP Blvd., Building 176
Honolulu
HI
96818808 725-5360808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
20100504024804
None
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http://www.coris.noaa.gov/metadata/records/html/cred_toad_ofu_olosega_oes0402_2004.html
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